Machimosaurus is an extinct genus of teleosaurid crocodyliform from the Late Jurassic (Kimmeridgian and Tithonian). The type species, Machimosaurus hugii, was found in Switzerland. Other fossils have been found in England, France, Germany, Portugal and Switzerland. Machimosaurus was not only both the largest teleosaurid and thalattosuchian, but with a length exceeding 9 metres (skull length 1.5 m), it was the largest crocodyliform of the Jurassic.